A group of New Zealand bikers has crossed the Demilitarised Zone (DMZ) dividing North and South Korea.

The bikers are led by New Zealand businessman and philanthropist Gareth Morgan who has taken part in many challenging bike rides across the world raising money for charity and writing books about his adventures.

In the latest challenge the group are riding the 9,000-kilometre journey from the Russian city of Magadan aiming to traverse the mountain "spine" of the Korean peninsula, from Mount Paektu in the North to Mount Halla in the South.

The group received a warm welcome as they crossed the border into South Korea met by a "huge media circus" on their arrival.

Gareth Morgan has told Asia Pacific they cleared customs expecting to just go on their way, "they said have a look at the top of that building...and on the top of the building was just this massive array of television cameras and photographers."

"I didn't know if the reception in the South would be friendly or hostile but it was amazingly friendly of course."

Only 24 hours before the group was due to cross the DMZ, a communication breakdown meant the transition from North to South may not have been so smooth.

The North Koreans weren't confident that their counterparts in the South would uphold their end of the deal.

"They said to us we can't be sure this is going to work, we want you to take additional food...we are going to drop you off in the middle of the zone and whether or not they are going to pick you up we will leave you there...we dont want to be accused of not doing what we said we'd do,' says Mr Morgan.

The group began their journey in Russia's far east, then made their way west across the Siberian mountains, around the border with China, until finally they dropped into North Korea.

They've has been blogging their experiences along the way, and now having passed successfully from the North to the South, Gareth Morgan has a message for those back home.

He says the West needs to rethink its ideas about Korea, "the imagery that you get from this almost concerted effort to demonise the place...it that it must be like one massive prison camp, nothing could be further from the truth."

He acknowledges North Korea is an authoritarian regime, but says preconceptions that the people are starving are actually not true.

He says the group found people were eating well and local crops were healthy.

Farming is self-sufficient, labour intensive but very productive.

The problem is that the country's sanctions mean there are no reserves - a facet Gareth Morgan says could lead to famine.

"When the crops go well everybody is happy and looks well fed, then suddenly you go from that to famine......because of the sanctions they are isolated."

Mr Morgan says that Koreans dress well noting that ladies wear gumboots with heels on them.

He says interaction between the group and ordinary North Koreans proved quite difficult.

Unlike in South Korea where people are free to chat he says that people in North Korea are all organised in work parties but say they did manage to meet a few North Koreans when they were at a beach resort.

The group were escorted throughout North Korea by a huge motorcade including a car with loudspeakers telling everyone what they were doing.

South Korea's Unification Ministry said it approved the crossing since the event would help promote peace on the Korean peninsula.

The two Koreas are currently taking tentative steps to revive a number of border projects, including reopening their Kaesong joint industrial zone.